1. Field of the Invention
The present invention relates to a foldable mechanism of a baby mesh bed, more particularly one, which has a relatively simple structure and low manufacturing cost, and which can be held in an in-use position relatively firmly so as not to fold accidentally to cause danger.
2. Brief Description of the Prior Art
A common baby mesh bed includes four foldable armrest mechanisms, which are arranged on four sides of an uppermost portion of the mesh bed respectively. Referring to FIG. 5, a currently existing foldable armrest mechanism 1 of a baby mesh bed includes two connecting tubes 41, a joining component 42, and a sliding piece 44. The joining component 42 has such a shape as to have an inverted U-shaped vertical section, and has a gap 421 on each of two ends of an uppermost portion thereof, and two opposite through holes 422 on two sides of a middle of an upper portion thereof.
The connecting tubes 41 are received in and pivoted to two ends of an upper portion of the joining component 42 at inward ends thereof. Each of the connecting tubes 41 has a through hole 411 on its inward end, and a V-shaped elastic piece 43 is partly held in the inward end of each of the connecting tubes 41, with two free ends thereof sticking out from the connecting tube 41; each said V-shaped elastic piece 43 has two fixing protrusions 431, which stick out through the through holes 411 of the connecting tube 41 respectively, and which will pass into the through holes 422 to prevent the connecting tube 41 from pivoting on the joining component 42 after the armrest mechanism 4 has been moved to a stretched in-use position.
Furthermore, the joining component 42 has a gap 423 on a middle of a lower portion, and a round joining hole 424 above the gap 423. And, the sliding piece 44 has a slot 442, and is held in the middle of the joining component 42. And, a joining rod 441 is passed through the round joining hole 424 and the slot 442 so that the sliding piece 44 can be moved up and down relatively to the joining component 42. The sliding piece 44 has a V-shaped gap 443, and a holding gap 444 under the V-shaped gap 443. A spring 46 is positioned in the holding gap 444, and joined at an upper end thereof to a joining piece 445 positioned under the joining rod 441 so that the sliding piece 44 is biased towards a lower position by the spring 446; the outer free ends of the V-shaped elastic pieces 43 will be received in an upper wider portion of the V-shaped gap 443 when the sliding piece 44 is in the lower position. Therefore, a lower narrower portion of the V-shaped gap 443 will come into contact with the outer free ends of the V-shaped elastic pieces 43 as soon as the sliding piece 44 is pushed to an upper position; thus, the V-shaped elastic pieces 43 are pressed to reduce their width, with the fixing protrusions 431 moving out of the through holes 422 of the joining component 42. Consequently, the connecting tubes 41 are no longer fixed to the joining component 42, and can be pivoted so as to move the armrest mechanism 4 into the folded position.
The above foldable armrest mechanism is found to have the following drawbacks:
1. The foldable armrest mechanism isn't safe to use; the fixing protrusions of the V-shaped elastic pieces can move out of the through holes of the joining component to no longer fix the connecting rods to the joining component, and the armrest mechanism can move to the folded position accidentally if the mesh bed is subjected to vibration.
2. The armrest mechanism has a relatively complicate structure, and high manufacturing cost because of adoption of the V-shaped elastic pieces, which are used to fix the connecting rods to the joining component, and can be disengaged from the joining component to allow the connecting rods to turn by means of pushing the sliding piece.
Therefore, it is a main object of the present invention to provide an improvement on a foldable mechanism of a baby mesh bed to overcome the above problems.